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Spring Testing:

WP tender Spring: 8.75 to 12.9 kg/mm, with the plastic internal lock out the spring probably is limited to 10kg when it's travel is limited.

WP main Spring: 8.1 - 9.4 kg/mm

So the Dual rate rear end setup from the factory is way off the mark....... essentially you have two springs with very similar poundage without any real progression as the tender is travel limited before it gets into the heavier rate.

not very smart...........

Comparison, After market Ohlins dual rate for the XC

Tender spring 10 - 11.25 kg/mm

Main Spring 6.5 - 7.3 kg/mm

this is the intermediate weight setup as recommend by Ohlins, it give a really plush ride in the XC and the SX and has a true progressive dual rate feature.

Racetech spring calculator recommends 7.5kg average rate for 200lb rider so we are in the right ball park here.

comparison stock spring stack vs Ohlins + zps helper on top, haven't finished machining of the collars etc to suit.

[attachment=3353:DSC00224.JPG]

Ohlins yellow spring is shorter which allows the space to install the ZPS tender spring

on the shock, preload full off, shock will compress and ride height is lowered, ideal for TT,

[attachment=3355:rear_sho...bach_sag.jpg]

preload can be adjusted full up, keeper collapses solid and shock is just like a std setup, but ride height can now be set anywhere between the two limits. This is what ZPS is all about...... and before anyone comments, yes the plastic travel limiter is on the wrong way around between the yellow and black springs..... this is just to give you and idea of where things are at now.

[attachment=3354:DSC00226.JPG]

the ZPS spring is an Eibach 60mm ID unit that fits on the top and will allow proper ZPS ride height adjustment. ZPS spring settles under the weight of the quad.

when finished I'll be able to have full travel just like the stock setup ( ZPS preloaded to fully compression as in the last photo, but will have the open of being able to lower the rear ride height by around -3" for smoother tracks / TT)

Due to the Zero preload it maybe necessary to go with the next heavier springs in the ohlins range, this will be a try it and see.....

what's not shown is the machined go between for the zps spring / black spring, this prevents coil bind on the zps spring, basically a copy of the GNCC go between that comes in the Ohlins GNCC kit, cut to suit.
 

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Can you leave the plastic limiter upside down or will you need to machine the one side shorter? if so how much shorter?

Id also like to hear about how you figure out the kg/mm of springs and apply it to figuring out what spring rate you need

it would greatly be appreciated Thanx

~Chad
 

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Discussion Starter #4
I had all new sleeves and platforms machined up to my specs.

I used the Ohlins spring set for the XC and followed thier recommendations on springs rates and cross checked to what Race tech state for the main spring in their online spring calcluator.

Works great. Now to get the front sorted...........
 

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Hey Kiwi. I need a link or let me know where to go for rear springs. I will be running Fox fronts and I weigh in at a fat 140(155 with gear). So I need o lighten that be-ach up in the back a little.

Thanks buddy!
 
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